uncia

[uhn-shee-uh] /ˈʌn ʃi ə/
noun, plural unciae
[uhn-shee-ee] /ˈʌn ʃiˌi/ (Show IPA)
1.
a bronze coin of ancient Rome, the 12th part of an as.
2.
(in prescriptions) an ounce of weight or volume.
Origin
1685-95; < Latin: a twelfth part, akin to ūnus one; cf. inch1